1. Field of the Invention
The invention relates to a method and apparatus for measuring out-of-plane displacement or deformation in the field of solid mechanics.
2. Description of the Related Art
There are several techniques for measuring out-of plane displacements (W) that are generally utilized. The techniques determine the topology of a specimen surface i.e., its deviation from a plane surface. In mechanics, the techniques are used to measure the topography of initially flat surfaces to evaluate warpage caused by load, temperature, humidity, age or other variables.
Shadow moiré is a method which is widely used for out-of-plane displacement measurements in the field of solid mechanics.